Error message when you try to log on to Windows Server 2003 or to Windows 2000 by using the IP address as the user name: �The specified target is unknown or unreachable�

When you try to log on to Microsoft Windows Server 2003 or to Microsoft Windows 2000 Server by using an IP address as the user name, you receive an error message that is similar to the following:Note You may also experience this problem when you use a thin client program that uses the IP address as the user name to automatically log on to Windows.

This issue occurs because the Kerberos client that is included in Windows Server 2003 and in Windows 2000 does not allow interactive logon when you use an IP address as the user name.

To work around this issue, log on to the computer by using the user principal name (UPN) logon format. For example, use the following UPN format:Note X.X.X.X can be your IP address.